Dubnium

Dubnium is atom number 105 — every Dubnium atom has exactly 105 protons in its center, and that number is what makes it Dubnium and nothing else. Its symbol is Db. At room temperature it is a solid.

Dubnium is a chemical element with symbol Db and atomic number 105. It is named after the town of Dubna in Russia (north of Moscow), where it was first produced. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, dubnium-268, has a half-life of approximately 28 hours.

Summary from the source dataset, derived from Wikipedia (CC BY-SA 3.0) · original article

Dubnium sits in period 7, group 5 of the d-block. Its 105 electrons fill shells of 2, 8, 18, 32, 32, 11, 2 — written as *[Rn] 5f14 6d3 7s2. Its electronegativity is — on the Pauling scale. The outermost shell holds 2 electrons — the ones that do all the chemistry.

Full configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d3
Electron affinity: — kJ/mol · Electronegativity (Pauling): —
Density: 29.3 g/cm³ · melts — · boils —

Values exactly as published — see where the data comes from.